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Angle-resolved photoemission spectroscopy (ARPES) is a widely used characterization technique in condensed matter physics, providing direct access to the single-electron spectral function of crystals, including their electronic band structure and Fermi surface. Measuring the band structure of novel quantum materials has been fundamentally important for determining, for example, nontrivial band topology, as in topological insulators, Weyl semimetals, and Dirac semimetals, or for identifying new classes of ma

Disordered materials under an imposed forcing can display creep and aging effects, accompanied by intermittent, spatially heterogeneous dynamics. We propose a testable microscopic description of these phenomena, based on the notion that as the system ages, the density of local barriers that enable relaxation displays a slowly evolving gap. As a result, the relaxation dynamics is dominated by the activation of the lowest, extremal tail of the distribution. This framework predicts logarithmic creep, as well a

Episodic autobiographical memory retrieval (EAM) is characterized by the vivid sense of re-experiencing past events. While doing so, different viewpoints over the scene can be taken, often referred to as the field or observer perspectives. However, the precision with which individuals can accurately reconstruct their original viewpoint over an event, within the field perspective, has not yet been characterized. Here we developed a task and continuous implicit measure to quantify this ability (viewpoint retr

Episodic autobiographical memory (EAM) retrieval is often accompanied by autonoetic consciousness (ANC) â the feeling of â re-experiencingâ past events. A large body of work shows that such recollection is supported by cortical reinstatement: the reactivation, at retrieval, of sensoryâ perceptual systems that were engaged at encoding. Yet, most evidence concerns visual and auditory signals, leaving unanswered the question of whether and how the motor system participates in remembering. Across this the

We study the average density of resonances (DOR) for a semi-infinite disordered chain, coupled to the outside world by a (semi-infinite) perfect lead. A set of equations is derived, which provides the general framework for calculating the average DOR, for ...

Condensation of exciton polaritons in semiconductor microcavities takes place despite in-plane disorder. Below the critical density, the inhomogeneity of the disorder limits the spatial extension of the ground state. Above the critical density, in the presence of weak disorder, this limitation is spontaneously overcome by the nonlinear interaction, resulting in an extended synchronized phase. In the case of strong disorder, several non-phase-locked condensates can be evidenced. The transition from a synchro

Using strong-disorder renormalization group, numerical exact diagonalization, and quantum Monte Carlo methods, we revisit the random antiferromagnetic XXZ spin-1/2 chain focusing on the long-length and ground-state behavior of the average time-independent ...

We have investigated the doping mechanism of pentacene with iodine and its impact on the structure and on the electronic properties of single crystals, powders, and thin films in a large range of iodine concentration up to six iodine per pentacene (PEN) molecule (I/PEN = 6). Three regimes of doping have been identified. In the low doping regime I/PEN < 0.05, the pristine pentacene structure of single crystals is maintained. Electron spin resonance (ESR) evidences a Pauli susceptibility, that is, the charact

Recent high-resolution photoemission results on high-T-c superconductors and other low-dimensional systems solve some critical issues but also open new fundamental questions. A recent breakthrough enabled us to clarify the interplay of conflicting periodicities in photoemission data. thus legitimizing the photoemission analysis of crystals with super-periodicities. On the other hand, results on the role of doping and of intentional disorder in Bi2Sr2CaCu2O8+x single crystals raise questions about the origin

We summarize some of the main results on photoemission spectroscopy in the field of high T-c superconductivity, beginning with a discussion of several open questions. We then briefly analyze our experiments that illustrate the role of doping and of intentionally introduced disorder (by electron bombardment) in Bi2Sr2CaCu2O8+x single crystals.

Nickel-aluminium intermetallics constitute interesting systems for the study of irradiation-induced phase transformations (order → disorder, amorphization) and production of defects. Irradiation of ordered intermetallics may induce disorder or amorphization depending on the projectile characteristics, irradiation conditions and chemical and physical properties of the target. The behavior of the various intermetallic compounds of the nickel-aluminium system with respect to electron and ion irradiation has be

The ab-plane optical reflectance of single crystal of Bi2Sr2Ca(Cu1-xNix)(2)O8+d, for x = 0.0215, has been measured from 80 to 40 000 cm(-l) (10 meV-5 eV) and at temperatures between 20 and 300 K. Through Ni substitution, the optical conductivity shows a broad peak at about 400 cm(-1), which grows in intensity and shifts to lower frequency as the temperature is reduced. We suggest that this peculiar low-frequency feature is associated with the significant disorder induced by Ni impurities. Analysis of the co

Thirteen years ago, late in 1986, several groups confirmed striking claims of the famous paper by Bednorz and Muller [see Z Phys. B, vol.64, p.189 (1986)] that announced the discovery of high-Tc superconductivity in cuprates. Some 60000 papers later, we are still struggling to understand the high-Tc oxide superconductivity. We present some of the most relevant recent experiments and discuss some open questions across rather complex electronic phase diagram; we also note an important role of un-intentional a

We used thermal neutron irradiation to produce disorder in Bi-2212 single crystals (T-c = 85 K), at a constant carrier density. The irradiated samples were insulators. High-temperature superconductivity with a lower T-c than prior to irradiation could be restored by a low-temperature annealing. We performed angle-resolved photoemission investigation on both unannealed (insulating) and annealed (superconducting) samples in order to study the corresponding changes in electronic structure. We observed a strong

We have irradiated by thermal neutrons single crystals of the Bi-2212 high T-c superconductor. The irradiated samples are insulators, but they regain high T-c superconductivity after an annealing in He at 450-550 degrees C. Depending on irradiation doses and annealing parameters, we obtained two insulators, with more or less disorder, and two superconductors with different values of T-c. We performed resistivity, a.c. susceptibility and angle resolved photoemission studies (ARPES). The coherent quasiparticl

The full experimental evidence of fine structure in disordered superlattices is reported. The experimental results agree with the numerical predictions, thus indicating that this effect is related to residual coupling between adjacent identical wells in the case of Anderson localization. This feature indicates an intrinsic difference between disorder-induced and electric-field induced localization, where no spectral fine structure can be observed in the strong localization limit. Copyright (C) 1996 Elsevier

The interplay of disorder effects and exciton-exciton interactions in the four-wave-mixing process in quantum wells is investigated. Experiments are performed employing femtosecond and picosecond pulses to have either good temporal or good spectral resolution. It is shown that the localisation of excitons is of primary importance in the generation of the nonlinear signal. It is shown which states contribute and how to the FWM process.

The pancreatic islet β-cell autoantigen of relative molecular mass 64,000 (64K), which is a major target of autoantibodies associated with the development of insulin-dependent diabetes mel-litus (IDDM) has been identified as glutamic acid decarboxylase, the biosynthesizing enzyme of the inhibitory neurotransmitter GABA (γ-aminobutyric acid). Pancreatic β cells and a subpopulation of central nervous system neurons express high levels of this enzyme. Autoantibodies against glutamic acid decarboxylase with a h

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Impact of static disorder on quasiparticle spectra: Debye-Waller, mean free path, and potential fluctuation effects

Thermal Avalanches Drive Logarithmic Creep in Disordered Media

Viewpoint Retrieval as a Behavioral Proxy for Episodic Re-experiencing

"Re-membering" your life: Motor contributions to episodic autobiographical memory and autonoetic consciousness

Statistics of resonances in a semi-infinite disordered chain

Synchronized and Desynchronized Phases of Exciton-Polariton Condensates in the Presence of Disorder

Correlation amplitude and entanglement entropy in random spin chains

Electronic and structural evidences for charge transfer and localization in iodine-doped pentacene

High-T-c superconductivity: new issues from photoemission data

Photoemission experiments on high-T-c superconductors: Recent progress and some open questions

The order-disorder transformation and microstructure evolution in nickel-aluminium intermetallics after heavy-ion irradiation

ab-plane optical properties of Ni-doped Bi2Sr2CaCu2O8+delta

Properties of high-Tc cuprates: some recent results and open questions

Irradiation-induced disorder in high-T-c cuprates: electronic band structure study

The effect of deliberately induced disorder on the electronic structure of the Bi-2212 high T-c superconductor

Anderson and Stark localization in superlattices: Residual coupling and fine structure

Influence of Disorder and Exciton-Exciton Interactions on 4-Wave-Mixing in Quantum-Wells

Identification of the 64K autoantigen in insulin-dependent diabetes as the GABA-synthesizing enzyme glutamic acid decarboxylase